F-35 Cancelled, then what ?
JSF Fan - No.
Just a realist. I think the program has been poorly handled, is overbudget, and is trying to turn a pigs ear specification wish list into a silk purse. On the other hand they seem to be largely succeeding.
- The unit cost is no-where near as bad as most of the media detractors suggest.
- The kinematic performance is probably its worst aspect (compromised by the design requirements making it short and fat).
- The avionics and SA provided by EOTS and DAS is a strong positive.
- The LO (VLO) nature of the airframe will bring advantages.
- The airframe in the US inventory will be replacing a handful of airframes that are rapidly running out of air hours and approaching obsolescence. As such I don't believe it will suffer the same magnitude of cuts from orders to numbers accepted as the F-22 did.
- It's a new developmental airframe - as such it will encounter problems - and usually the problems will be overcome (eg: Dave C's tailhook) some won't be - transonic acceleration target 9at least until they uprate the donk). I cannot think of any other complex manufactured product of any sort that does not have issues (car recalls, 787 Li-Ion batteries, F-111's well documented issues etc).
The problem is there is an aspect of the 'Emperor's New Clothes' here. The airframe's (very) average kinematic performance seems to be being compared with other 4th and 4.5th gen contemporaries and it comes up short in most yardsticks (I think APA used the term 'clubbed like a baby seal'). Yet, advances of the sensors, sensor fusion and LO characteristics are supposed to well and truly turn the tables on the contemporary opponents. As the generic you and I don't have access to the classified performance data of this airframe and sensors, we need to accept the Lockmart's line on this. Or, trust that the senior people in the defence forces of 8 of the best airforces in the world have made the correct choice. Call me an optimist, but I believe you don't get to senior ranks in the ADF for example, without knowing a thing or two about air combat and how these jets will be employed. These are the same people who do have access to the classified stuff and have decided that this aircraft, despite the cost and kinematic issues is well worth buying over existing 4th and 4.5th gen options.
I suppose my yardstick for comparison is when we grunts had our trusty L1A1 SLR's replaced by the F88 Steyr in 1988. My initial skepticism was replaced by admiration that the little space age looking plastic gun was a better weapon for most infantry purposes than the old trusty SLR. I still have a soft spot for the L1A1, but realize that there are better weapons available today.
So, not a blind fan of the 'Dave', but accept that as I am not privy to all of the info of the beast I have to trust that the people that have the access and are selecting the airframe know what they are doing. They certainly know more than most of the uninformed commentary I have seen (APA, certain haters on other websites etc).
Just a realist. I think the program has been poorly handled, is overbudget, and is trying to turn a pigs ear specification wish list into a silk purse. On the other hand they seem to be largely succeeding.
- The unit cost is no-where near as bad as most of the media detractors suggest.
- The kinematic performance is probably its worst aspect (compromised by the design requirements making it short and fat).
- The avionics and SA provided by EOTS and DAS is a strong positive.
- The LO (VLO) nature of the airframe will bring advantages.
- The airframe in the US inventory will be replacing a handful of airframes that are rapidly running out of air hours and approaching obsolescence. As such I don't believe it will suffer the same magnitude of cuts from orders to numbers accepted as the F-22 did.
- It's a new developmental airframe - as such it will encounter problems - and usually the problems will be overcome (eg: Dave C's tailhook) some won't be - transonic acceleration target 9at least until they uprate the donk). I cannot think of any other complex manufactured product of any sort that does not have issues (car recalls, 787 Li-Ion batteries, F-111's well documented issues etc).
The problem is there is an aspect of the 'Emperor's New Clothes' here. The airframe's (very) average kinematic performance seems to be being compared with other 4th and 4.5th gen contemporaries and it comes up short in most yardsticks (I think APA used the term 'clubbed like a baby seal'). Yet, advances of the sensors, sensor fusion and LO characteristics are supposed to well and truly turn the tables on the contemporary opponents. As the generic you and I don't have access to the classified performance data of this airframe and sensors, we need to accept the Lockmart's line on this. Or, trust that the senior people in the defence forces of 8 of the best airforces in the world have made the correct choice. Call me an optimist, but I believe you don't get to senior ranks in the ADF for example, without knowing a thing or two about air combat and how these jets will be employed. These are the same people who do have access to the classified stuff and have decided that this aircraft, despite the cost and kinematic issues is well worth buying over existing 4th and 4.5th gen options.
I suppose my yardstick for comparison is when we grunts had our trusty L1A1 SLR's replaced by the F88 Steyr in 1988. My initial skepticism was replaced by admiration that the little space age looking plastic gun was a better weapon for most infantry purposes than the old trusty SLR. I still have a soft spot for the L1A1, but realize that there are better weapons available today.
So, not a blind fan of the 'Dave', but accept that as I am not privy to all of the info of the beast I have to trust that the people that have the access and are selecting the airframe know what they are doing. They certainly know more than most of the uninformed commentary I have seen (APA, certain haters on other websites etc).
Mk 1...
"The unit cost is nowhere near as bad as its media detractors suggest".
Not sure which detractors you are talking about, or which definition of cost you're using, but as a generic statement this does not mean much. Unit production cost of the B (under discussion here) is by any definition about three-quarters of what RAND estimated the F-22 would have cost in continued production, if everything goes to plan and at triple-digit total F-35 production rates.
The F-35A is still much more expensive than the Super Hornet in production costs, whether total procurement, flyaway or (LockMart's favorite) tow-away (no engine). All this is in the latest official estimates, the 2011 SAR.
"We need to accept LockMart's line on this... trust the professionals in the air forces."
Er, no. Not when progress has been retrograde since 2008 (IOC now appears to be further in the future than it was then) and the projected US acquisition bill (R&D and procurement) has gone up $40 million a day in constant dollars since the SDD contract was signed. Or when people who were briefing 2013 IOCs in 2009 are still employed.
Also - I would try to avoid terms like "haters" around here. Save it for the sites infested with hairy-palmed basement-dwelling pizzavores, where BTW you will find much more spluttering invective aimed at JSF critics than the other way around.
"The unit cost is nowhere near as bad as its media detractors suggest".
Not sure which detractors you are talking about, or which definition of cost you're using, but as a generic statement this does not mean much. Unit production cost of the B (under discussion here) is by any definition about three-quarters of what RAND estimated the F-22 would have cost in continued production, if everything goes to plan and at triple-digit total F-35 production rates.
The F-35A is still much more expensive than the Super Hornet in production costs, whether total procurement, flyaway or (LockMart's favorite) tow-away (no engine). All this is in the latest official estimates, the 2011 SAR.
"We need to accept LockMart's line on this... trust the professionals in the air forces."
Er, no. Not when progress has been retrograde since 2008 (IOC now appears to be further in the future than it was then) and the projected US acquisition bill (R&D and procurement) has gone up $40 million a day in constant dollars since the SDD contract was signed. Or when people who were briefing 2013 IOCs in 2009 are still employed.
Also - I would try to avoid terms like "haters" around here. Save it for the sites infested with hairy-palmed basement-dwelling pizzavores, where BTW you will find much more spluttering invective aimed at JSF critics than the other way around.
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Anxiety remains in the DoD about the effects of the upcoming across-the-board spending cuts, the F35 is still one of the main targets.
Budget cuts would reduce flying hours, F-35 orders: Air Force | Reuters
Budget cuts would reduce flying hours, F-35 orders: Air Force | Reuters
WASHINGTON | Wed Feb 6, 2013 3:18pm EST
(Reuters) - The U.S. Air Force will have to curtail its orders for Lockheed Martin Corp's F-35 fighter jet, restructure a $52 billion tanker contract with Boeing Co and reduce its flying hours by 18 percent if lawmakers do not avert impending across-the-board spending cuts, the service told Congress on Wednesday.
The Air Force, in a draft presentation to Congress, said it faced shortfalls of $1.8 billion in war funding and $12.4 billion overall if Congress does not forestall the cuts, known as sequestration, which are due to take effect on March 1.
(Reuters) - The U.S. Air Force will have to curtail its orders for Lockheed Martin Corp's F-35 fighter jet, restructure a $52 billion tanker contract with Boeing Co and reduce its flying hours by 18 percent if lawmakers do not avert impending across-the-board spending cuts, the service told Congress on Wednesday.
The Air Force, in a draft presentation to Congress, said it faced shortfalls of $1.8 billion in war funding and $12.4 billion overall if Congress does not forestall the cuts, known as sequestration, which are due to take effect on March 1.
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Just finished re-reading Bill Gunston's chapter on the MD A-12 Avenger in "Jet Bombers"
talk about deja-vue!! It was going to replace the A-6 and various other strike aircraft on a "Better than one-to-one basis"
of course it ran wayyyyyyy over budget and was going to be well under spec so they cancelled it - and TBH it didn't affect matters very much
talk about deja-vue!! It was going to replace the A-6 and various other strike aircraft on a "Better than one-to-one basis"
of course it ran wayyyyyyy over budget and was going to be well under spec so they cancelled it - and TBH it didn't affect matters very much
Last edited by Heathrow Harry; 7th Feb 2013 at 13:48.
Since the X-32 has entered the thread, did the wrong design win?
Was the X-32 a worse design and/or Boeing a more risky company, I know it looked ugly but was it more likely to mature in to the required platform?
Was the X-32 a worse design and/or Boeing a more risky company, I know it looked ugly but was it more likely to mature in to the required platform?
I am in no doubt whatsoever that the right PWSC won. Boeing's initial concept was simple, but, in my view, not up to the job. So the design for the X-32 showed a lot of painful development to turn an over-simple concept into a workable aircraft (i.e. Boeing kept finding problems and having to add things to the design to fix them, resulting in a design that got more and more complex). The final aircraft aircraft could be called many things, but in comparison to the X-35, "elegantly simple" would not be one of them. In my engineering judgement anyway. The PWSC also seemed to get more complex as it progressed, notably so when presented for the final assessment. The usual game was "aren't there more pipes and nozzles than last time?", but that wasn't the only game as "so how does that actually work then?" was also fun.
So, "Harrier-like"?, well not really since the Harrier doesn't have a conventional jet-pipe that can be closed off with a massive diverter valve to shunt the exhaust out of other big nozzles for V/STOL. "No mess with doors"? it certainly had doors to do V/STOL (covering/uncovering the main lift nozzles as well as elsewhere). "A lot less complex than the one used in the F35"? Well, count the nozzles. X-35B and F-35B have four, to do lift, propulsion and control. I have actually forgotten how many the X-32B had (you can probably find some graphics on elsewhere on the internet), or the PWSC (may have been the same number, but certainly not all doing the same thing so I think it ended up as a different number again), but in both cases it's a lot more than 4. The Harrier has a lot more than 4 also (4 lift/propulsion and then a herd more for control, with associated, very clever, piping). So, just 4 nozzles to do everything. Elegantly simple.
Do a Hover - it avoids G
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X-32/X-35
Over 40 different jet VSTOL concepts flown around the world have taught us one thing:
For it to be successful the design/layout of any jet lift aircraft must keep the hot engine efflux out of the intake
This is not a ‘nice to have’ performance enhancing thing but is as important to STOVL as not having wings that drop off is to ordinary flight.
The X-32 incorporated a dam of cool air exhausting down behind the intake that it was hoped would keep the hot air from moving forward towards the intake. It worked at model scale but not at full scale.
The X-35 deliberately had more flow from the front fan than the rear nozzle which stopped the hot efflux moving forward.
For it to be successful the design/layout of any jet lift aircraft must keep the hot engine efflux out of the intake
This is not a ‘nice to have’ performance enhancing thing but is as important to STOVL as not having wings that drop off is to ordinary flight.
The X-32 incorporated a dam of cool air exhausting down behind the intake that it was hoped would keep the hot air from moving forward towards the intake. It worked at model scale but not at full scale.
The X-35 deliberately had more flow from the front fan than the rear nozzle which stopped the hot efflux moving forward.
Last edited by John Farley; 7th Feb 2013 at 19:31.
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From where we sat, far away in another land, quite an interest was taken in the 32/35 contest. Being on the other side of the fence, so to speak, we were quite relieved when the Lockheed submission was chosen. The Boeing bid, while of the face of it simpler, was technologically more advanced - the thermoplastics for the wing and the overall wing design were particularly innovative.
Mr Farley is, as ever on these matters, quite correct. Hot gas ingestion in an aeroplane in the hover is never a desirable attribute. But having established that simulation data did not translate into the real world, we believe that Boeing were well on their way to resolving this issue. Why they weren't given the opportunity to implement this was beyond our understanding
In truth, the 32 was killed by its looks. So instead of an aircraft with 20 years development potential you now have the opportunity to purchase the phenomenally expensive bastard child of the F-22 with questionable performance characteristics (which get worse by the day...) and a myriad of problems which were entirely foreseeable but ignored because 'it looked good'.
Have you ever wondered why the Chinese, despite having access to most of the 35's program data, have thought it wise only to copy selected elements of its design?
Mr Farley is, as ever on these matters, quite correct. Hot gas ingestion in an aeroplane in the hover is never a desirable attribute. But having established that simulation data did not translate into the real world, we believe that Boeing were well on their way to resolving this issue. Why they weren't given the opportunity to implement this was beyond our understanding
In truth, the 32 was killed by its looks. So instead of an aircraft with 20 years development potential you now have the opportunity to purchase the phenomenally expensive bastard child of the F-22 with questionable performance characteristics (which get worse by the day...) and a myriad of problems which were entirely foreseeable but ignored because 'it looked good'.
Have you ever wondered why the Chinese, despite having access to most of the 35's program data, have thought it wise only to copy selected elements of its design?
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John,
Far be it from me to doubt that the lift-fan was a good way to deal with the potential danger of hot air ingestion but I seem to remember that the X35 also had similar issues, most notably on one of its final proving flights right before the DoD decided in favour of the F35 when on the last vertical landing it also suffered an engine stall right before touch down.
I think it also happened on the hover tests initially executed over the specially constructed pit.
As far as the RR lift-fan goes, even up until today it is a very complicated and far from trouble free system with more than one part with limited life-expectancy performance, shaft, gears and bearings come to mind here, we're not even speaking about the 3,000Lbs of death weight it comes with and a life expectancy for the whole engine set up only half that for the normal engine ,4000 iso 8000, lift-fan only 200hrs.
The Boeing design also could use its simple 2D exhaust, coming from the VTOL version, on the entire range of models and use it as a 2D nozzle in flight, a simplified F22 system.
The hot air ingestion was somewhat of a design challenge, but nowhere near unsolvable within an acceptable time-frame.
Also the way I see it, and comment would be more than welcome, the X32 system would be a lot better than the 35 when used in slow forward speed regimes,no more barnyard sized doors, complicated rear swivelling nozzles and extra potential of engine/fan troubles when ingesting the inevitable bird(s) passing by, that lift-fan is basically just one extra oversized airsucking hoover.
I doubt that operating it in a similar fashion (improvised forward operating bases ) as the old Harrier will be such a good idea, something the MARINES ceratainly plan on doing, no?
All in all the X32 , in my (fairly worthless) opinion, is a typical example of 'a future lost through a lack of vision'.
Far be it from me to doubt that the lift-fan was a good way to deal with the potential danger of hot air ingestion but I seem to remember that the X35 also had similar issues, most notably on one of its final proving flights right before the DoD decided in favour of the F35 when on the last vertical landing it also suffered an engine stall right before touch down.
I think it also happened on the hover tests initially executed over the specially constructed pit.
As far as the RR lift-fan goes, even up until today it is a very complicated and far from trouble free system with more than one part with limited life-expectancy performance, shaft, gears and bearings come to mind here, we're not even speaking about the 3,000Lbs of death weight it comes with and a life expectancy for the whole engine set up only half that for the normal engine ,4000 iso 8000, lift-fan only 200hrs.
The Boeing design also could use its simple 2D exhaust, coming from the VTOL version, on the entire range of models and use it as a 2D nozzle in flight, a simplified F22 system.
The hot air ingestion was somewhat of a design challenge, but nowhere near unsolvable within an acceptable time-frame.
Also the way I see it, and comment would be more than welcome, the X32 system would be a lot better than the 35 when used in slow forward speed regimes,no more barnyard sized doors, complicated rear swivelling nozzles and extra potential of engine/fan troubles when ingesting the inevitable bird(s) passing by, that lift-fan is basically just one extra oversized airsucking hoover.
I doubt that operating it in a similar fashion (improvised forward operating bases ) as the old Harrier will be such a good idea, something the MARINES ceratainly plan on doing, no?
All in all the X32 , in my (fairly worthless) opinion, is a typical example of 'a future lost through a lack of vision'.
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X-32 Hover Pit Troubles Video
For 'kbrockman' X-32 JSF first vertical (hover) landing
"Uploaded on Mar 16, 2007
The X-32 (Boeing's entry into the Joint Strike Fighter competition) can be seen here landing vertically like a helicopter (or, rather, like a Harrier). As we all know, Lockheed won the competition with the X-35/F-35, but Boeing's airplane is still very cool, as you can see. For more X-32 videos (including VTOL, or hovering flight), go to:
http://www.youtube.com/profile_videos?user=BoeingX32JSF
Looks like the X-32B had some Hover Pit Troubles. Click thumbnail for big pic:
Pic from Video mentioned above.
"Uploaded on Mar 16, 2007
The X-32 (Boeing's entry into the Joint Strike Fighter competition) can be seen here landing vertically like a helicopter (or, rather, like a Harrier). As we all know, Lockheed won the competition with the X-35/F-35, but Boeing's airplane is still very cool, as you can see. For more X-32 videos (including VTOL, or hovering flight), go to:
http://www.youtube.com/profile_videos?user=BoeingX32JSF
Looks like the X-32B had some Hover Pit Troubles. Click thumbnail for big pic:
Pic from Video mentioned above.
Last edited by SpazSinbad; 8th Feb 2013 at 15:17. Reason: Clarification - screengrab from video
even up until today it is a very complicated and far from trouble free system with more than one part with limited life-expectancy performance, shaft, gears and bearings come to mind here, we're not even speaking about the 3,000Lbs of death weight it comes with and a life expectancy for the whole engine set up only half that for the normal engine ,4000 iso 8000, lift-fan only 200hrs.
The hot air injestion problem is a show stopper, but the lift fan also produces twice the vertical lift for the energy used.
So the 2700lb dead weight is easily outweighted by the 'free' 10,000lb of lift it produces. That 7000lb is the entire VLBB and spare that the X-32 could never have. The C require's more 'dead weight' to land on a carrier the old fashioned way...
I'd say the lift fan is a brilliant solution to two major problems with vertical landing.
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First, nobody said it isn't a brilliant piece of technology.
But ,as the F version, it still needed a complete redesign for it to be anywhere near useful and even up until today it's got some big issues.
So much for the law of conservation of energy.
Btw, the fact that it actually needs every single pound of that massive amount of vertical thrust is more a testimony of the overall state of the F35 and its obesity problems.
The death weight lift-fan isn't a small part of the vicious circle the F35 has seemed to spiral in to.
A common design -> space needed for the lift-fan +weight -> bulky design needed -> Extra weight to build a strong enough frame to compensate for all that extra weight -> Stronger thus heavier engine needed -> more fuel needed to achieve range , extra weight -> repeat circle.
they should have called the F35 the F35 Hippopotamus, it can be used on land and water, packs a good punch but is quickly out of breath, needs an enormous amount of food is rather bulky and weighs a ton (or 2 or3).
Structural issues remain to be a problem up until today and even with the most powerful engine available used in any of the fighters worldwide still doesn't make it anywhere near as nimble as the fighters it is supposed to replace.
PS I fully understand that the system used in the F32 (with the redesigned and much lighter tail) was also going to be a challenge for the VTOL version because of the lower amount of vertical thrust at hand but it still would've been a better solution even if it might not have gotten as much payload available as the F35, certainly not when solely used as a VTOL rather than the usually V/STOL it in reality really is.
More wing=lift and lighter Aircraft combined with the strong engine and the Ramp present at the UK CVG (and Italy, and Spain/Australia) would've made for one hell of a F32B, iso wanting the F35, the MARINE corps should have opted for fitting their LHA/D's with ramps (eg like the one used on the JUAN CARLOS which doesn't protrude too much into the available deck area ) and be done with it.
MARINES/NAVY carrier politics bit them both in the ass again it seems.
The way I see it is that the MARINES/UK needs where too much of a factor in the choice between the F32 or F35 ,this again combined with the knowledge that the F35 was Lockheed's last opportunity to remain a fighter constructor in the long run ,the F22 by then already was on the chopping block with 339 iso the original 750 with prospects on more reductions ahead.
But ,as the F version, it still needed a complete redesign for it to be anywhere near useful and even up until today it's got some big issues.
the lift fan also produces twice the vertical lift for the energy used.
So the 2700lb dead weight is easily outweighted by the 'free' 10,000lb of lift it produces.
So the 2700lb dead weight is easily outweighted by the 'free' 10,000lb of lift it produces.
Btw, the fact that it actually needs every single pound of that massive amount of vertical thrust is more a testimony of the overall state of the F35 and its obesity problems.
The death weight lift-fan isn't a small part of the vicious circle the F35 has seemed to spiral in to.
A common design -> space needed for the lift-fan +weight -> bulky design needed -> Extra weight to build a strong enough frame to compensate for all that extra weight -> Stronger thus heavier engine needed -> more fuel needed to achieve range , extra weight -> repeat circle.
they should have called the F35 the F35 Hippopotamus, it can be used on land and water, packs a good punch but is quickly out of breath, needs an enormous amount of food is rather bulky and weighs a ton (or 2 or3).
Structural issues remain to be a problem up until today and even with the most powerful engine available used in any of the fighters worldwide still doesn't make it anywhere near as nimble as the fighters it is supposed to replace.
PS I fully understand that the system used in the F32 (with the redesigned and much lighter tail) was also going to be a challenge for the VTOL version because of the lower amount of vertical thrust at hand but it still would've been a better solution even if it might not have gotten as much payload available as the F35, certainly not when solely used as a VTOL rather than the usually V/STOL it in reality really is.
More wing=lift and lighter Aircraft combined with the strong engine and the Ramp present at the UK CVG (and Italy, and Spain/Australia) would've made for one hell of a F32B, iso wanting the F35, the MARINE corps should have opted for fitting their LHA/D's with ramps (eg like the one used on the JUAN CARLOS which doesn't protrude too much into the available deck area ) and be done with it.
MARINES/NAVY carrier politics bit them both in the ass again it seems.
The way I see it is that the MARINES/UK needs where too much of a factor in the choice between the F32 or F35 ,this again combined with the knowledge that the F35 was Lockheed's last opportunity to remain a fighter constructor in the long run ,the F22 by then already was on the chopping block with 339 iso the original 750 with prospects on more reductions ahead.
Originally Posted by kbrockman
the F35 Hippopotamus, it can be used on land and water, packs a good punch but is quickly out of breath, needs an enormous amount of food is rather bulky and weighs a ton (or 2 or3).
Do a Hover - it avoids G
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kbrockman
I was unaware of that. Having talked to the pilots of both I feel that the event you describe happened with the X32 not the X35.
As to your concerns about about the conservation of energy the ability to hover some 25% more weight using the same basic engine results from a difference in propulsive efficiency between propellers and jets at low speeds.
but I seem to remember that the X35 also had similar issues, most notably on one of its final proving flights
As to your concerns about about the conservation of energy the ability to hover some 25% more weight using the same basic engine results from a difference in propulsive efficiency between propellers and jets at low speeds.
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As to your concerns about about the conservation of energy the ability to hover some 25% more weight using the same basic engine results from a difference in propulsive efficiency between propellers and jets at low speeds.
.
I was unaware of that. Having talked to the pilots of both I feel that the event you describe happened with the X32 not the X35.
Still I seriously doubt it would be a show stopper, keep in mind that the X32 was only a prototype, as far as I remember it didn't have the extra overhead auxiliary vent doors for the regular engine when used in hover like on the X35.
They got the Harrier working , I fail to see why the F32 wouldn't have worked out.
Overhead doors, a longer inlet ala F8 Crusader or even an emergency water injection system (for a minute or 2) are all possible (just some random ideas at the top of my head), the Boeing/P&W engineers probably know a whole lot more possible solutions.
F-35B - Lift Fan
Last edited by kbrockman; 8th Feb 2013 at 09:35.
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F35 performance? No worries
LM has reacted to the performance issues following the recent relaxation of some performance specifications.
IN FOCUS: Lockheed claims F-35 kinematics
Their point is that the performance of a tooled-up 4th gen aircraft will be inferior to a clean F35, with internal weapons. Now, if the UK's F35B's are in the strike role, they will be trying to evade using their low-observable advantage. But if they are in carrier defence mode they will have to engage, and ideally BVR. AMRAAM is being cleared for use, so is that what the UK will have to use, unless Meteor can be shrunk to fit? And either will limit your internal weapons load. Or you carry more externally and accept both stealth and performance penalties - which is not the point. So, in defensive mode, might the UK's F35's be out-gunned, even if not out-flown? Less of an issue for the USN who will have other fighter defence options with Super Hornet; but the UK will not; and the USMC may not either if they don't have any USN carriers close by.
Maybe smaller longer range weapons will be developed so stealth can be maintained and enough missiles carried - but that must be a demanding technical challenge.
So I am not particularly reassured by FM's response. Strikes me as more spin than substance but I hope I am wrong.
LF
IN FOCUS: Lockheed claims F-35 kinematics
Their point is that the performance of a tooled-up 4th gen aircraft will be inferior to a clean F35, with internal weapons. Now, if the UK's F35B's are in the strike role, they will be trying to evade using their low-observable advantage. But if they are in carrier defence mode they will have to engage, and ideally BVR. AMRAAM is being cleared for use, so is that what the UK will have to use, unless Meteor can be shrunk to fit? And either will limit your internal weapons load. Or you carry more externally and accept both stealth and performance penalties - which is not the point. So, in defensive mode, might the UK's F35's be out-gunned, even if not out-flown? Less of an issue for the USN who will have other fighter defence options with Super Hornet; but the UK will not; and the USMC may not either if they don't have any USN carriers close by.
Maybe smaller longer range weapons will be developed so stealth can be maintained and enough missiles carried - but that must be a demanding technical challenge.
So I am not particularly reassured by FM's response. Strikes me as more spin than substance but I hope I am wrong.
LF
Pretty much the point I was exploring in my post 976 http://www.pprune.org/7677549-post976.html
Even relatively small changes to the spec CAN have disproportionate effects on operational effectiveness. The only way to find out is to re-run the trials using the new parameters. I cannot (and am not) saying that the aircraft no longer meets our requirements, I'm saying we don't know whether it does or not. But I would be very surprised, given the magnitude of the downgrade, if there weren't a huge change in overall effectiveness.
Even relatively small changes to the spec CAN have disproportionate effects on operational effectiveness. The only way to find out is to re-run the trials using the new parameters. I cannot (and am not) saying that the aircraft no longer meets our requirements, I'm saying we don't know whether it does or not. But I would be very surprised, given the magnitude of the downgrade, if there weren't a huge change in overall effectiveness.
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I wouldn't lose too much sleep, if I were you, How many planes fly at M1.2 dry with nearly 5,000 lbs of weapons?
F-35 May Miss Acceleration Goal | Defense News | defensenews.com
The F-35 transonic acceleration specifications were written based on clean-configuration F-16 Fighting Falcon and F/A-18 Hornet fighter, Burbage said.
But unlike the Hornet or the F-16, the F-35 has the same configuration unloaded as it does loaded with weapons and fuel, Burbage said.
“What is different is that this airplane has accelerational characteristics with a combat load that no other airplane has, because we carry a combat load internally,” Burbage said, the F-22 Raptor notwithstanding.
Even fully loaded, the F-35’s performance doesn’t change from its unencumbered configuration, he said.
In the high subsonic range between Mach 0.6 to Mach 0.9 where the majority of air combat occurs, the F-35’s acceleration is better than almost anything flying.
Air Force Lt. Col. Eric Smith, director of operations at the 58th Fighter Squadron at Eglin Air Force Base, Fla., and F-35 test pilot, said that flying the aircraft is a thrilling experience.
“I can’t even explain the adrenaline rush you get when you light the afterburner on that thing,” Smith said. “The acceleration is much better than an F-16.”
But the F-35’s aerodynamic performance is not what makes the jet special, Smith said. The F-35 powerful sensors and data-links and how that information is fused into a single coherent and easy to use display are what will make the jet an effective warplane.
Burbage added that while the F-35 is designed as a supersonic fighter, it’s not optimized for the extremely high supersonic speeds that the Raptor was designed to operate at.
F-35 May Miss Acceleration Goal | Defense News | defensenews.com
The F-35 transonic acceleration specifications were written based on clean-configuration F-16 Fighting Falcon and F/A-18 Hornet fighter, Burbage said.
But unlike the Hornet or the F-16, the F-35 has the same configuration unloaded as it does loaded with weapons and fuel, Burbage said.
“What is different is that this airplane has accelerational characteristics with a combat load that no other airplane has, because we carry a combat load internally,” Burbage said, the F-22 Raptor notwithstanding.
Even fully loaded, the F-35’s performance doesn’t change from its unencumbered configuration, he said.
In the high subsonic range between Mach 0.6 to Mach 0.9 where the majority of air combat occurs, the F-35’s acceleration is better than almost anything flying.
Air Force Lt. Col. Eric Smith, director of operations at the 58th Fighter Squadron at Eglin Air Force Base, Fla., and F-35 test pilot, said that flying the aircraft is a thrilling experience.
“I can’t even explain the adrenaline rush you get when you light the afterburner on that thing,” Smith said. “The acceleration is much better than an F-16.”
But the F-35’s aerodynamic performance is not what makes the jet special, Smith said. The F-35 powerful sensors and data-links and how that information is fused into a single coherent and easy to use display are what will make the jet an effective warplane.
Burbage added that while the F-35 is designed as a supersonic fighter, it’s not optimized for the extremely high supersonic speeds that the Raptor was designed to operate at.
Last edited by JSFfan; 8th Feb 2013 at 17:37.
Originally Posted by JSFfan
I wouldn't lose too much sleep, if I were you, How many planes fly at M1.2 dry with nearly 5,000 lbs of weapons?
I am very pro getting the new system onto our inventory. But only if it really can deliver what we need.
Thank you for sharing the SUBJECTIVE impressions of a number of third parties with us. I don't know what they prove.
I would be interested to hear your thoughts on an objective review on where we stand with this now.
Last edited by Courtney Mil; 8th Feb 2013 at 17:45.
